In Kubernetes, applications usually log to STDOUT, which is captured and managed by Kubernetes.
To access the log, use the kubectl -n NAMESPACE logs PODNAME command.
Useful options include --tail (specify the number of lines), --since and --follow.
Instead of specifying the PODNAME, you can also use a selector:
-l app.kubernetes.io/name=gentics-cms for Gentics CMS
-l app.kubernetes.io/name=gentics-mesh for Gentics Mesh
-l app.kubernetes.io/name=gentics-portal-php for Gentics Portal | php
-l app.kubernetes.io/name=gentics-portal-java for Gentics Portal | java
-l app.kubernetes.io/name=gentics-activiti for Gentics Task Management App
-l app.kubernetes.io/name=keycloak for Keycloak
-l app=mariadb for MariaDB
-l chart=elasticsearch for Elasticsearch
Gentics CMS uses different logfiles for specific tasks, as is detailed in the Gentics CMS guide.